#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define n 1000
int main()
{
    FILE *fp = fopen("data.in", "r");
    if((fp=fopen("data.in", "r")) == NULL)
    {
        printf("Fail to open!\n");
        exit(0);
    }
    char str[n+1];
    while(fgets(str, n, fp) != NULL)
    {
        int i;
        for(i=0; i<strlen(str); i++)
            if(str[i]>='A'&&str[i]<='Z') str[i] += 32;
        printf("%s", str);
    }
    fclose(fp);
    return 0;
}
